So much of the landscape that holds clues to the Chicago region’s prehistoric past has either been paved over or plowed under. That’s why a relatively pristine area located within Midewin National Tallgrass Prairie has archeologists excited.
Some 40 years ago, a team from Northwestern University discovered artifacts on the site, such as pottery sherds, that were confirmed to be 1,000 years old. The objects suggested the presence of some sort of early settlement, dating to the same Mississippian period as the Cahokia Mounds in southwestern Illinois, a UNESCO World Heritage Site.
Now, with more advanced tools at their disposal, scientists from the Field Museum and University of Illinois-Chicago are revisiting the scene to explore it more intensively.
“(The Mississippian) is a real interesting period, when people are starting to settle down a little bit more,” said Bill Parkinson, curator and professor of anthropology with the Field Museum and UIC, who’s one of the lead researchers on the project.
“Most Native American groups were very mobile up even through the time of European contact, but this is the time period when they really do start settling down and staying in one place a little longer. But we really don’t have a great understanding of that in northern Illinois,” he said. “The site is really just a window into a bigger world of how the region changed over time. It’s sort of our first step into understanding that bigger picture.”
The area under investigation straddles a creek that flows into the Kankakee River near its convergence with the Des Plaines into the Illinois River.
“Throughout history and pre-history, this was a really important part of the world. These are major rivers in northern Illinois, and the Illinois is the gateway to the Mississippi, which is the gateway to all of the South,” Parkinson said. “So we’re located at a real critical area here.”
But in terms of a written record of the region’s inhabitants, there’s a void up until substantial numbers of Europeans entered the territory, around the time the I&M Canal was built, he said. Traces of native peoples’ existence, long buried at Midewin, could help fill in those gaps.
This past October, a group that included Parkinson; Jamie Kelly, head of anthropology collections at the Field; and UIC professor Mitch Hendrickson, headed to Midewin, shovels in hand.
“Because of COVID, none of us have been able to do field work in two years, which is like depravation for an archaeologist, to not be able to be in the field,” Parkinson said. “So we were excited to get out there.”
Their first order of business was to re-find the site initially located by their predecessors back in the 1980s, which wasn’t nearly as simple as it sounds.
The Northwestern team had, in the course of their survey, dug nearly 8,000 holes, called shovel tests. “You go and you sink a shovel in the ground and you see if there’s stuff in it,” Parkinson explained. “And then you go 10 meters from that place, and you sink another shovel in the ground.”
The Field-UIC group was in search of the holes that had yielded the ceramic artifacts, but remember, GPS wasn’t something the average person had access to in the ‘80s, Parkinson said.
“They were working in a big area,” he said. “It’s on maps, but it’s a bit of a needle in a haystack.”
Assisted by what Parkinson called a “boatload of students from UIC,” as well as museum staffers who volunteered their time, the Field team conducted shovel tests of their own. After several days they hit paydirt, turning up pottery fragments and stone tools that matched the age of the Northwestern discovery.
“Now we’ve got GPS points. We know where sort of the center of the site is,” Parkinson said.
With the exact coordinates locked, he said, the team can focus on developing a broader research plan. The intention is to return in the spring with equipment that wasn’t available 40 years ago, specifically a magnetometer, which allows archeologists to scan the surface and “see” underground to identify objects below.
The idea is to disturb as little earth as possible. “When you dig an archeological site you destroy it, you’re taking it out of the ground. Nobody can ever go back and re-dig it,” Parkinson said. With magnetometry, “When we do reach the point where we’re doing a larger scale excavation, we can be very surgical and very deliberate.”
Among the questions the Field team is hoping to answer as it digs deeper: How many people lived at the settlement? Was it temporary or permanent? Who were they? What were they doing?
Scientists with specialities in fields like archaeobotany (the study of past human-plant interactions) will be brought in to sift through soil samples for things like seeds in order to gain a better sense of what plants were present, either in people’s diets or as part of the landscape.
“These are the kind of things that are going to take the next phase of research to get to,” Parkinson said. “Those are exactly the people we can bring in to tell us, you know, what were people eating, what were they fishing for? How reliant were they on corn, which is a huge game changer in North America, when corn takes off.”
That a site so rich in potential exists 50 miles from Chicago is remarkable considering how much change has occurred in the region in just the past century.
“I can’t overemphasize how important it is to have a big tract of land like this,” Parkinson said.
At 20,000 acres, Midewin is the largest contiguous green space in the metro area. A sizable portion of that acreage is undergoing intense restoration, having been destroyed during its former life as home to the Joliet Arsenal, owned by the Department of Defense. At the same time, large swaths of unused land within the arsenal’s boundaries were protected from development.
In turning the arsenal over to the forest service, the federal government ensured the site’s future preservation, a boon to archeologists.
“It’s a special resource for us,” Parkinson said. “The way that we have, especially during the Industrial Age, modified the surface of the earth, we can’t go back, we can’t undo it. So those areas that we do have that are pristine, we really need to work to keep them pristine.”
For Parkinson, whose research more typically focuses on Europe, working on a site in his own backyard adds another layer of meaning.
“It’s super personal for me because I grew up in a tiny little town that was basically a bedroom community to the arsenal. Where we’re working is literally right across the Kankakee River from where my grandma’s cottage was. So this is really for me going back home,” he said.
He caught the archeology bug as a boy, stumbling across artifacts in the cornfields near his house. And now here he is, helping piece together the story of the people who made and used those objects.
“What we have here is a real unique opportunity to talk about how humans used this landscape over the last 10,000 years. And we’re starting with this project, with this one site,” Parkinson said. “And this is just the beginning.”